I know it'll come as a complete surprise to everyone on Do3D that the idea of making an Iron Man suit was one of the things that drove me to get into 3D printing. I decided early on that I wanted to focus on a suit that had moving parts, the functionality as it were, more so than a suit that looks exactly like any particular movie suit. As such I've had to design, engineer, and re-engineer many parts over and over again. While I'm not as far along on my suit-building as I'd like, I've come a long way, and have a bit of knowledge to share for anyone following a similar path.
The MP Select Mini was what I needed to get my toes wet. A cheap printer ($200 new when I got it) that came pre-assembled, could easily fit anywhere in a small apartment and be moved out of the way for guests, could print PLA and theoretically ABS (bed caps at 75C, which is low for ABS), it's biggest limitation was build volume. At 120x120x120mm, it's one of the smallest printers out there. It was plenty big enough for printing servo enclosure s and small mechanical systems, but I knew I wasn't going to be able to print any exterior suit pieces without a lot of pain. I could get longer pieces by printing at a diagonal, and I did that a few times to squeeze the absolute most out of this tiny printer. Also, the controls for this printer always felt backwards. You had to control everything with a nob, and if you wanted to move the print head to the right you had to spin the nob to the left.
In the picture you can see a keyboard for scale. It's tiny, well deserving of the name "Mini".
CAD software - Sketchup
Sketchup ($0) was something I'd been using for a long time. It was familiar, comfortable, and I could design anything I wanted with ease. The problem with Sketchup was that I couldn't edit that design with ease. My editing workflow ended up being something along the lines of copy and paste the previous version, cut off the part that needed to be changed, and rebuild that part from scratch.
The need for an upgrade
The CAD software let me down first. In testing different mechanisms, I must have had 30 or more iterations of the parts all in the same file, and the program was bogging down. Each edit was painful to make, and I needed something new. I also ended up making a design mistake that my printer couldn't handle. The diagonal of my printer is about 170mm, so I figured I could print a semi-circle on it with a diameter of 165mm... not realizing the entire time I was designing that the semi-circle would cross outside my build volume. When I realized my mistake, I tried brainstorming different ways to get even more build volume (such as printing at a 3D diagonal instead of just a 2D diagonal), and started looking around at other 3D printers I could rent out, but ultimately decided that I needed to buy my own upgrade.
My Mk 2 Setup
CAD software - Fusion 360
Sketchup failed first, so it was the first thing to be replaced. Fusion 360 ($0) was that replacement. While it's certainly easier to make multiple changes at once, I'd be lying if I said the change was easy. Fusion 360 is great if you are pretty positive you know what you want and if you're very careful with constraints (rules that position parts of your design based on other parts of your design). If you forget those constraints, or if you need to make a drastic change, then the whole model can blow up in your face. Granted, it's still usually easier to fix a Fusion 360 model that completely broke 1 time in 50 than it is to keep re-building Sketchup models, but there is certainly a learning curve. Every time I think I've got things perfectly designed I end up needing to change one dimension dramatically and things fall apart, but I am absolutely getting better with it and wouldn't go back to Sketchup for designing parts.
Printer - Artillery Sidewinder X1
The Artillery Sidewinder X1 (might also be called the Envovo Sidewinder X1, they're not sure if they're doing a rebranding or not) is a massive upgrade in printer. I bought mine on Gearbest.com during a flash sale for $380, and they got it to my doorstep in 3 days without charging for shipping. This printer has a bed of 300x300x400mm, enough to literally print a 1:1 scale model of my Monoprice Select Mini. While I could have the MP Select Mini on my work bench and still use the workbench, this behemoth eats the whole desk space, and isn't easily moved. Assembly was pretty straight forward, but with a bigger printer there's more to double check and fine tune to get perfect prints, and I'm still working through that process. There's one thing that's an unexpected plus for the Sidewinder: the bigger printer is ridiculously quiet! With the MP Select Mini I could hear it printing from halfway across the house, but with the Sidewinder I've had moments where I physically had to go into the room and watch the machine to make sure it was even printing because it's that quiet. The only time I've heard it in the next room is when the slicer coded a long travel at high speed, but I bet I can dial that down. It's also a direct drive printer, so I should be able to print flexible filament now. The heated bed really ramps up in temp, with the thermometer reaching temp very quickly (the bed itself needs just a little bit longer to evenly heat up). The touchscreen controls are much faster and easier to navigate, and the assisted bed leveling (where the printer moves the print head to where it needs to check for level) and large nobs under the print bed are hands down better than the full manual with Alan wrench leveling that had to be done on the Select Mini. And speaking of wrenches, the Sidewinder X1 came with all of the tools you need to service it, which is about 3 or 4 different sizes of Alan wrenches and a normal wrench, as well as spare cables, rollers, screws, a thumb drive, and even a spare multicolor LED (they have it mounted right next to the hot end), all of it in a very tidy bag. Even though I'm still in the early stages of using this printer, I love it. I just wish we could share the desk!
You can see the same keyboard from the Mini's picture here as a comparison. The machine is massive, but it feels like the smallest profile they could do for the build volume.
Slicer: Cura ($0). I messed with some of the other free slicers, but Cura won me over because it was fast and easy to use. Just as Cura's come a long way, I'm sure the others have as well, and they may even have features that are better than Cura's, but I don't find myself wanting much more than what Cura offers.
Filament: I haven't paid much attention, other than to notice not all "silver" PLA is made equal. I started out with Tianse Silver PLA, which has a nice metallic look to it (a slightly dark gray color, kind of like a gunmetal), but when I ran out I just bought some Inland Silver PLA from Microcenter. The Inland is disappointing, and in most lights just looks like Light Gray. I looked on Amazon for more Tianse Silver, but I think they're transitioning that color from PLA to PLA Pro? Either way it's not on Amazon anymore and I don't think they sell straight from their website.
Inland "Silver" (Left) vs Tianse Silver. You walk away from the Tianse Silver remembering it as metallic looking, but the Inland you just remember as gray. The one on the right was printed on the Monoprice Select Mini (each ring is made up of two halves), and is about the biggest thing I could possibly print on that machine.
Projects: I'm working on my own mechanical designs to fit inside a suit. The above pictures were tests for
different Mk 6 inspired forearms (which would be loaded with mini-rockets, a la Iron Man 2 and Avengers). The design to the left is an even earlier prototype that was wired up for an electronics test. Not sure when I'll get all the designs finalized enough that I can move on, but it's an enjoyable project all the same.